Date: Mon, 21 Jan 2002 22:54:38 -0500
Reply-To: Bob Allen <b.t.allen@HOME.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Bob Allen <b.t.allen@HOME.COM>
Subject: Re: '80 Westfalia-- best way to drive over passes
Content-Type: text/plain; charset="iso-8859-1"
DRIVE LIKE YOU STOLE IT
----- Original Message -----
From: "G. Matthew Bulley" <gmbulley@BULLEY-HEWLETT.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, January 21, 2002 10:27 PM
Subject: Re: '80 Westfalia-- best way to drive over passes
> As a type IV veteran of 19 years, (multiple busses, 914's, and a Vanagon
> Westfalia) I can tell you this is a tough motor to kill. Your concern
> is warranted though; like any mechanism, even the Type IV motor can
> fail.
>
> Most T4's fail at the valve seat... I'd guess 90% drop a valve seat, or
> (sometimes) burn a valve or a piston, almost all due to overheating. The
> trick to keeping the head s cool is [exactly as you presume] keeping the
> motor spinning over freely, and quickly so that the fan is displacing
> the waste heat from the heads. Having the oil pump and oil cooler
> drawing heat out of the motor helps as well, but the slower the motor is
> turning over, the less efficiently these are working.
>
> Something I read years ago (source lost to the sands of time) told me
> that the T4 fan is at its most efficient at 4,200-4,800 rpm. Above and
> below that you are reaching diminishing returns, either because the fan
> is spinning more slowly, or because fluid dynamics at the molecular
> level along the cylinder and head metal disallows any further heat
> transfer, even if more air is passing by. Does that make sense? Okay...
> Further, you are at the peak of both your HP and torque curves in this
> range, so the motor is at its most efficient.
>
> So if you keep you motor wound up pretty nicely on steep grades, but not
> screaming, you are doing the right thing, even if you are creeping along
> in 2nd at 28 mph. I've been over Wolf Creek pass a couple times, (13k)
> and a number of others in WY, NM, and AZ around 11k at all temperatures,
> with no problems whatsoever. Simply relax, don't "Lug" the motor, and
> enjoy the trip, even if everyone is passing you.
>
> Often times you will be passing them if it is hot enough, and they push
> their beast too hard.
>
> All of this assumes that you have all the pieces of your original
> tinware in place, as well as a full and complete edge seal around the
> motor, and a decent seal around the license-plate access door. If any of
> this is missing, all bets are off.
>
> From historic, walkable Mount Olive, NC,
>
> G. Matthew Bulley
> Bulley-Hewlett
> Corporate Communications
> Business: www.bulley-hewlett.com
> Alliance: www.ntara.com
> Home: www.MountOliveNC.info
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf
> Of phil hans
> Sent: Monday, January 21, 2002 7:23 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: '80 Westfalia-- best way to drive over passes
>
> Hi everyone,
>
> What are people's opinions of the best way to drive
> over steep passes with the vanagon? What I mean is,
> what is the best way to do it to bring the smallest
> amount of harm to the drive train of this van? If you
> are going over a steep pass in a mountain for 50
> minutes, should you just go slow, like 30 mph? The
> slower you go, the easier it is on the transmission
> and the axles, etc. Or, is it better to go over the
> pass at 80% of the speed of a particular gear, like,
> either 30 mph in 2nd gear, or 48mph in 3rd gear? If
> you push the vanagon, will you hurt the engine? I've
> managed to go over passes alright, but I was
> interested in an authoritative opinion on this
> subject. Obviously, these vehicles don't have the
> most powerful engines in the world, but is the tranny
> and the axles stronger, or is the whole drive train
> weak? Is just the engine the weak part?
>
> The idea is not to take this vehicle over a ton of
> passes, but if you can't avoid it, what's the best
> approach? I have an aircooled with a rebuilt engine
> with 30,000 miles on it. It is doing fine and I want
> to keep it that way. Sorry for overwriting. :-)
>
> Thanks, Phil Hanson
>
>
>
>
>
>
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